The Discovery Scanner
The discovery scanner, for those unfamiliar with the terminology, is CCP's new name (as of Odyssey) for the overall probing system. It shows you the anomalies and signatures in the system you are in. It mostly displays in the Probe Scanner window, which you can see screenshots of below. The Probe Scanner window shows anoms and sigs in a spreadsheet. However, the discovery scanner also displays in the main window. You can also see anoms and sigs out in space.
Note that the discovery scanner is a distinct and different thing than the "dscanner" aka the "directional scanner". Even though both have a "d" and a "scanner".
Game Mechanics Used
|Probe Scanner window|
There is a second way to get new information, but this is per-ship, not everybody at once. A ship gets an update whenever it enters a system (duh). It also gets an update when the player clicks certain buttons on the probe scanner window. Since this must be done repeatedly to stay up to date, similar to dscanning, I call it "strobing" the discovery scanner. (I don't think that is a common usage, but you are invited to steal it.)
|After clicking "Show Anomalies"|
Other people strobe by clicking a "Show" button in the bottom right of the Probe Scanner. You can also get it by clicking the spreadsheet's column labels (which sorts by that column). There are other ways too. Basically, almost anything you click on the Probe Scanner will cause an update.
Using the Discovery Scanner to Stay Safe
So how do you use the discovery scanner to harvest resources safely in wspace? Relatively safely, anyway. First, you want to get your system to be as safe as possible. Zip it up! If you cannot zip it up, or are too lazy, then at minimum you want a sound picket at every wormhole. Of course, every sound picket means one less pilot who could otherwise be doing something. And it makes a single point of failure: if your picket guy happens to go to the bathroom for a few minutes, you have no backup. But that's your call.
Now that you're zipped and/or fully picketed, you can start doing whatever you want very safely. Mining, for example. However, you must stay there at the keyboard and strobe the discovery scanner frequently. How often? No less than a minute, and I would probably want more. 30 seconds is about right.
If you do see a new signature, and you are out in space doing stuff, immediately warp to safety. (The same is true, of course, if you have a wormhole picket who hears or sees anything unexpected.) Once you have safed up, get a scanner ship out and see what the new signature is. If it is a wormhole, it is very likely that someone will come through. Prepare yourself. Indeed, it is very likely that someone has already come through it. If it is not a wormhole (which is unlikely, but it does happen), no problem. Get back out there and continue doing your thing.
Note that a fleet can use a fleet/wing/squad commander to fleet-warp the whole fleet. Thus, it is possible to make just one guy at a time responsible for the fleet's safety. The commander sits there strobing the discovery scanner, while everyone else watches movies in another window, goes to the bathroom, etc.